An interesting way of instantiation

When you do not have access to instantiate a class through a factory or so, one possible way is to declare an inner private class which extends the class to be instantiated.

For example, we have a class "Vehicle" which is marked abstract and hence cannot be instantiated directly. There is a "VehicleFactory" which is meant for giving an instance of this class.

Now, I want to to create an instance of "Vehicle" class in my class without using VehicleFactory. Here is how:

public class Myclass{

private MyVehicle myVehicle = new MyVehicle();

private class MyVehicle extends Vehicle{
}

public static void main(String args[]){
Myclass myClass = new Myclass();
myClass.myMethod();
}

public void myMethod(){
myVehicle.drive();
}
}

Can you think of some advantage of this kind of usage ?